Posted
by
Unknown Lamer
on Tuesday July 26, 2011 @02:10PM
from the as-above-so-below dept.

derGoldstein writes "Discovery posted an interesting story of how X-rays that are used by astronomers for determining the various chemical abundances inside stars could also potentially be used for more effective radiation therapy: 'Radiation treatment is a coarse instrument at best, since it destroys surrounding healthy cells as well as cancerous tumors. Much research is underway for targeted methods to reduce the collateral damage and attack just the cancer cells, including embedding nanoparticles inside tumors ... Nahar and Pradham envision a prototype device capable of generating x-rays (gzipped PDF) at the key frequencies to trigger a flood of low-energy electrons in platinum and gold, based on their computer simulations. Gold or platinum nanoparticles would amass naturally in cancerous tumors in the body, and could then be zapped with the focused x-ray beam.'"

Question is do the cancer cells naturally accumulate gold and platinum when other cells do not, and if so, why?

If they did, we could mine cancer patients and they could finally pay for their therapy. I agree, where did THIS little bit come from? I suppose you can try to tag the cancerous particles with gold or palladium, but there are plenty of other toxic therapies that would be improved by targeting only cancer cells. The trick is to figure out how to select cancer cells and leave the rest of the body alone and do it in the body and not the test tube.

Platinum complexes are a standard treatment for many cancers. They intercalate in DNA, especially in rapidly dividing cells, and block DNA transscription.

These contain isolated (but complexed) metal atoms, though, not nanoparticles. I do not know whether these compounds could also serve as effective electron sources on X-ray irradiation, or whether they might form nanoparticles in a tumor cell, or outside dead cells after killing them in their primary therapeutic function.

These contain isolated (but complexed) metal atoms, though, not nanoparticles. I do not know whether these compounds could also serve as effective electron sources on X-ray irradiation

Most ranges of X-rays (possibly overlapping into the extreme UV) are caused by transitions in either direction between an electron in one of the innermost couple of electron shells and a "free" electron (absorb an X-ray and an electron gets kicked out ; have a free electron then relax into that hole and an X-ray gets emitted).

Most of the targeting is based on making the beam mainly hit the tumor that they want to hit. Methods include using a beam (you can't really focus x-rays), and making that beam enter form various angles so that the surrounding cells get a lower dose than what the beam hits. But that is very crude. It's like trying to kill your kidney while leaving your other organs intact by bashing you with a baseball bat from all sides instead of just bashing right at the kidney.

Yep, I know someone working on their Phd on this exact topic and said that the Auger electron yield was lower than expected, in addition to other problems handling cancer cells (prematurely dying/temperature regulation/nanoparticles showing up where they shouldn't/etc/etc).

Also, this PDF talks about a tunable monochromatic X-ray source as if they have to invent one. What the hell?? Just put a proposal in at a synchrotron.... if the spectral purity is too poor, find a facility that makes use of a DCM and a

Summary does not follow from headline. What does mundane x-ray therapy have to do with astronomy? No, I don't want to RTFA for that. You teased it in the headline, re-teased it in the first sentence of the summary, then explained it not. I have to read this summary in a sing-song version of an Australian accent with half my brain removed, while dangling shiny things in front of my face, in order to get the mood it's written in.

They scientists discovered a unique property of certain x-rays that will cause metals like gold and platinum to emit electrons that can kill cancer but the electrons aren't powerful enough to damage neighboring cells. This discovery was made by astrophysicists who were doing computer simulation of emission spectrum of all the different elements so they could get a better understanding of the composition of stars. Now if you actually read the article you would have known this, it isn't very long and is a fairly easy read even for someone who isn't in the field.

It's actually in the summary as well:
"...X-rays that are used by astronomers for determining the various chemical abundances inside stars..."
So he complained after reading the headline, and part of the summary. In true Slashdot fashion.

No, I read the whole summary, and that is nothing but a recapitulation of the premise in the headline. It says nothing interesting about cosmic x-rays and treatment.

And yes, I certainly could RTFA, but then why write a summary at all, if it's not going to summarize the main point in the headline so that I don't have to RTFA just to get the main point in the headline?

The summary was perfectly succinct, and even featured the salient bit of information you were bitching about. You have to do more than skim read it and then immediately leap to the "reply" button though, which is clearly what you did.

Well, the headline is wrong too. X-rays are not used for stargazing. Stargazing is a passive only endeavor. X-rays are emission only deal.

I actually knew that when I submitted this, but it was the closest headline I could fit. The problem is that you can only fit so many characters into a headline, so when I submit stories I often have to truncate the title to a point where it's no longer technically accurate. I think they have to limit the title length so it "fits" in RSS feeds (as one line, rather than a split sentence).

The first thing to go is grammar, and if it's not short enough by then you have to abbreviate anyway you can.

Scientists studying stars discovered that certain metals emit certain wavelengths of X-rays. From that they deduced they could implant these metals preferentially in tumors, then use X-rays at those wavelengths to emit electrons from the metal to kill the tumor."

With appropriate hyperlinking to TFA pretty much anywhere in there.

So now you'll get whacked with a rolled-up newspaper for being sensationalist in the headline, but not by me. And I'd probably want to read TFA

So now you'll get whacked with a rolled-up newspaper for being sensationalist in the headline, but not by me.

Exactly -- If I submitted a story with the title "Cosmic X-Rays Cure Cancer", if it even got posted, the first comment would be "the title implies that X-rays from space cure cancer!". I try to submit stuff that will generate interesting discussion, so I try getting the gist of the subject in the summary, because I know most people don't RTFA.

In this case, It's not really about the fact that it was thought of by astronomers, but rather that it could advance radiation treatment (which is like a sledgehamm

The Mayo Clinic got to bill Medicare $1000/injection for my grandmother's weekly shots that were supposed to boost her red blood cells. After six months they couldn't justify it anymore, and turned her over to hospice care. She passed away a week later.

Sure, her doctors meant well, and were practicing the kind of medicine they were trained in...

The purpose is to surround the metals with a small layer of plasma. This plasma is what kills the cancer cells.

This plasma will only occur wherea) there is gold/platinumb) where they focus the X-rays. Focusing the X-rays is done just like your gamma knife: multiple beams from different directions, converging on the tumor.Since liver and kidneys are not radiated, you get no plasma there...

Most current cancer treatments already cost as much or more than the equivalent weights of precious metals. My mom's IV stuff alone was over $24,000 per bag, and there were a lot of bags. And anything that keeps the incredibly toxic substances away from your body is a plus. The chemo stuff is seriously harsh on people.

Cash in your tumors now! Tired of those old cancers lingering in your body, trying to kill you and wreck your life? Just zap those tumors with our finely-tuned X-rays, and send the biopsy to us for instant cash. Contact our website, and we'll send you a free postage-paid bio-hazard bag. What could be easier? With the price of gold skyrocketing every day, you'll take up smoking just to get in on this great offer!

They're not oblivious to that fact. That's the whole point. The aim is to get more effective therapy with lower doses of X-rays.If this plasma method only requires half the X-rays for the same effect, you will affect the healthy tissue 50% less.

A file that is actually a PDF (which is already compressed) that is a SINGLE FILE that is tarred but named with "ppt" in it, and stuffed into a useless subdirectory called "FB01" and then gzipped??? Um.... yeesh.

As a PhD candidate who works with noble metal nanoparticles on a daily basis, I have some issues with their work.

1. How do they plan to get the particles to "naturally" accumulate in tumors without some sort of surface coating; specifically one incorporating some sort of tumor sensing molecule?

2. If the nanoparticle is coated with some other molecule, do they still expect "low-energy" electrons to punch through without trouble? How low is "low-energy" anyway? In my experience, when dodecanethiol is attached